Code Q&A

A. Electrical metallic tubing (EMT), elbows, couplings, and fittings can be installed in concrete, in direct contact with the earth, or in areas subject to severe corrosive influences where protected by corrosion protection and judged suitable for the condition [358.10(B)]. According to the UL White Book (Category FJMX), "galvanized EMT installed in concrete on grade or above generally requires no supplementary corrosion protection." If the galvanized EMT is in a concrete slab below grade (such as a concrete floor of a basement), or emerges from concrete into earth, supplemental protection may be required.